The Site Reliability Engineering team, or SRE for short, is the team responsible for developing and maintaining Wikimedia's production infrastructure. Previously known as Technical Operations, they are in charge of making sure all Wikimedia's sites and services used by the general public (including MediaWiki and all associated services) run reliably, securely, and with high performance.

Additional documentation related to our infrastructure and the team's work can be found on Wikitech.

The Data Center Operations sub team is responsible for all of Wikimedia’s data center deployments and logistics as well as maintaining our presence in 8 locations across the world. They perform on-site work and maintain the full 5-year life cycle (specs, purchasing, physical install, break/fix and decommissioning) for all hardware.

This sub team focuses on building and maintaining our base platform (“metal cloud”) that forms the foundations upon which nearly everything else in our infrastructure builds upon. On top of our bare metal deployments, their responsibilities include (but are not limited to) configuration management systems, infrastructure automation, orchestration tooling, logging, metrics and monitoring as well as infrastructure security.

The Traffic sub team is responsible for the critical first layer of high-traffic infrastructure which now spans much of the globe, including our TLS termination and caching layers (nginx, Varnish), load balancing, DNS and our own network.

The Data Persistence sub team focuses on Wikimedia’s persistent data storage and retrieval systems, including (No)SQL databases, (distributed) object storage, file storage and backup systems. Today, this team consists of just our two database administrators, but the expectation is that this team will be built out in the near future with additional hands and expertise.

Finally, the Service Operations sub team takes care of public and “user-visible” services alongside Technology and Audiences teams. This means, for example, our MediaWiki platform, but also the newer (micro)services that comprise our stack. It also includes miscellaneous services and components that we rely upon (think Phabricator, mail systems, OTRS, etc…). The team is also building our new SOA service infrastructure based on Kubernetes.